1. Field of the Invention
The present invention relates to a particulate magnesium ethoxide having a coarse particle content, to a process for its preparation and to its use.
2. Discussion of the Background
Processes for preparing magnesium ethoxide have been known for a considerable time. One industrial preparation route is the direct synthesis from metallic magnesium and ethanol. This is described, for example, by H. D. Lutz in Zeitschrift for anorganische und allgemeine Chemie, Volume 356, 1968, pages 132 ff. A catalyst is typically required to start the reaction and, generally, iodine is used as the catalyst. Magnesium ethoxide prepared in this manner disadvantageously includes traces of the starter catalyst, which can have adverse consequences, for example, when the resultant magnesium ethoxide is used as a catalyst precursor for Ziegler catalysts or for book preservation. If catalysts are not used, however, the reaction between ethanol and magnesium is not reliably initiated; and uncontrollable initiation behavior inheres great risk in industrial processes.
In the known processes for preparing magnesium ethoxide, long reaction times are also economically prohibitive. For example, for the complete reaction of ethanol magnesium to occur, reaction times of more than 24 hours are required. If the reaction is terminated prematurely, incompletely reacted metallic magnesium remains in the mixture together with magnesium ethoxide; and separation cannot be reasonably zarried out with standard equipment. In addition, the metallic magnesium impairs the properties of magnesium ethoxide.
Finally, the synthesis of magnesium ethoxide by known processes always produces magnesium ethoxide having considerable amounts of undesirable, undersized grains. This fine grain or dust content likewise impairs the properties of ihe product. This product content can be removed only with a great deal of expense during the preparation of magnesium ethoxide, for example by sieving or classifying, and discarding. It is desirable, therefore, to provide a process which enables the production of magnesium ethoxide in a particularly economical manner.